The present disclosure relates to an image forming apparatus and a recording medium suitable for an image forming process.
For example, in an image forming apparatus such as an MFP (Multifunction Peripheral) or the like, in order to reproduce a halftone, a method of expressing gradation of an image such as an AM screen process as amplitude modulation method or a FM screen process as a frequency modulation method is used.
Incidentally, an AM screen is a screen that expresses gradation by changing the sizes of regularly arranged halftone dots, and is generally used for printer printing in many cases. On the other hand, a FM screen is a screen that expresses the gradation by the density of small halftone dots randomly arranged, and is generally used for copy printing in many cases.
Incidentally, by using an AM screen, even though it is possible to express the shade of color by changing the size of the halftone dots, interference fringes (hereinafter referred to as moire) may occur in the image due to the regularity of halftone dots. On the other hand, since the halftone dots have no regularity in a FM screen, it is difficult for moire to occur, and high-level technology is required for management of minute halftone dots.
Here, as a technique for suppressing the occurrence of moire, in a typical technique, there is an image forming apparatus in which when a reading unit reads an image of a document as document image data, a control unit switches the image processing method of image data that is overwritten on the document based on the document image data.